G Вegimbaeva^1,2 and N Pisnyy^1,2*

¹National Educational Institution, "Kazakhstan-Russian Medical University", Almaty, Kazakhstan
²"FOCUS Ophthalmological Center" LLP, Kazakhstan

*Corresponding Author: N Pisnyy, National Educational Institution, "Kazakhstan-Russian Medical University", and "FOCUS Ophthalmological Center" LLP, Kazakhstan

Received: March 27, 2024; Published: April 17, 2024

Abstract

Introduction: The relevance of the issue under consideration is explained by the continuously increasing number of patients after keratotomy who require cataract surgery. Cataract remains a relevant and significant problem in modern ophthalmic surgery. In the last decade, the number of patients undergoing cataract surgery after keratorefractive surgery has increased. Specifically, senile cataracts are increasingly becoming an indication for surgery in eyes that have undergone radial keratotomy.

Purpose of the Study: To evaluate the effectiveness of an optimized approach to calculating the optical power of intraocular lenses in patients after radial keratotomy, independent of clinical and anamnestic refractive data.

Materials and Methods of Research: The studies were carried out based on the results of clinical observations of 39 patients (61 eyes) who had previously undergone radial keratotomy (RK) for myopia and myopic astigmatism along with varying degrees of cataract maturity. The age of the patients ranged from 42 to 62 years, with an average age of 45.2 ± 6.4 years for the subjects.

Results of Our Own Research: As a result of clinical and diagnostic studies, an analysis was conducted of the data concerning the mathematical calculation of the preoperative corneal curvature value after RK, along with the clinical outcomes of predicted refractive outcomes of intraocular lenses in cataract patients.

Discussion: The clinical analysis of the 3rd generation formulas revealed that the calculated value of the effective lens position (ELP) is dependent on the radius of curvature of the cornea. This radius determines the depth of the anterior chamber and the distance of the optical part of the IOL from the posterior surface of the cornea.

Сonclusions: 1. The method of mathematical modeling of the optical parameters of the cornea after radial keratotomy can be used as an effective way to calculate the preoperative curvature of the cornea using keratotopographic data of its periphery, providing optimal accuracy in determining the optical power of the IOL. 2. Based on mathematical modeling data, there is a substantiated need to determine the effective position of the lens. 3. A comparative analysis of the refractive results of FEC in patients who underwent RK demonstrated the effectiveness of the double keratometry method. This approach enabled achieving maximum refractive accuracy within 1.15 diopters in 53.4% of cases.

Keywords: Double Keratometry Method; Radial Keratotomy (RK); Effective Lens Position (ELP)

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Citation

Citation: G Вegimbaeva and N Pisnyy. “A Research on the Efficiency of the Refined Method for Determining the Optical Power of Intraocular Lenses in Patients After Radial Keratotomy".Acta Scientific Ophthalmology 7.5 (2024): 21-26.

Copyright

Copyright: © 2024 G Вegimbaeva and N Pisnyy. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.